Rogowski Coil Thyristor Current Sensing for Isolated Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for measuring and controlling thyristor bridge circuits, such as using shunts, Hall Effect current sensors, and iron core transformers, are inefficient due to high voltage insulation failures, energy consumption, size, and cost, and do not provide a linear representation of current.
Innovation Solution
A system utilizing a Rowgoski coil in communication with a thyristor, integrated with a processor to determine alternating and direct current values and control the thyristor, including an analog to digital converter and serial output units for remote processor control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If shunts are used to measure current in thyristor bridge circuits, then current measurement is achieved, but insulation failures occur due to high voltage exposure and large energy consumption causes overheating
Solution Approach 1:
The patent introduces Rogowski coils as an intermediary measurement device that couples to the thyristor bridge circuit through magnetic coupling rather than direct electrical contact. This mediator approach allows current measurement without exposing measurement components to high voltage, eliminating insulation failure risks while maintaining measurement accuracy
Solution Approach 2:
The patent replaces the traditional shunt-based electrical measurement system with a magnetic field-based Rogowski coil system. This substitution eliminates the need for direct electrical connections through high voltage environments, using electromagnetic induction to transfer measurement information without physical exposure to hazardous conditions
2Measurement precision
If shunts are used for current measurement, then current measurement is achieved, but large amounts of energy are consumed causing overheating
Solution Approach 1:
The patent replaces resistive shunt-based measurement with electromagnetic induction-based Rogowski coil measurement. This substitution eliminates the I²R power losses inherent in shunt resistors, as the Rogowski coil operates passively through magnetic coupling without dissipating significant energy, thereby preventing overheating
3Measurement precision
If iron core transformers are used to measure large currents, then current measurement is achieved, but large and expensive components are required
Solution Approach 1:
The patent employs Rogowski coils that are significantly smaller, lighter, and less expensive than traditional iron core transformers. These coils can be easily manufactured and deployed without requiring large magnetic cores or complex winding structures, reducing both size and cost while maintaining measurement capability for large currents
Solution Approach 2:
The patent changes the measurement approach from using large iron core transformers to using compact Rogowski coils with air cores or minimal magnetic material. This parameter change in the measurement device structure eliminates the need for large magnetic paths and heavy construction, achieving the same measurement function with dramatically reduced size and weight
4Measurement precision
If Hall Effect current sensors are used to measure current, then current measurement is achieved, but a linear representation of current is not output and devices are larger and more expensive
Solution Approach 1:
The patent replaces Hall Effect sensor-based measurement with Rogowski coil-based electromagnetic induction measurement. This substitution inherently provides a linear relationship between the measured current and the induced voltage signal, eliminating the need for complex compensation circuits required by Hall Effect sensors to achieve linearity, while also reducing device size and cost
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system efficiently measures and controls thyristor currents with small, cost-effective components, providing a linear representation of current and enabling remote processor control, reducing the need for large and expensive equipment.
Implementation Method 1
Rogowski coil in operable communication therewith the thyristor
Data Source
AI summary
An exemplary embodiment includes a system for measuring and controlling a thyristor comprising a thyristor, a Rowgoski coil in operable communication therewith the thyristor, and a processor operative to receive signals from the Rowgoski coil, determine a direct current value of the thyristor, and control the thyristor.